Promises of charitable donations are, as we all know, enforceable without consideration. If you're looking for a good illustration of a withdrawn donation, consider the case of Florida International University, where a donor has withdrawn a $20 million pledge to the institution's new medical school.

Longtime FIU supporter Herbert Wertheim had promised $20 million dollars, and the school was planning on naming the school after him. (Yes, the naming rights would be probably be consideration so the charitable gift exception may not apply here.) But FIU balked at his request to allow him to pay it in four annual $5 million installments. On the telephone, the university president reportedly told Wertheim that he'd got the naming rights "on the cheap" and that the University could get $100 million for them. Wertheim apparently told the school that it would be unfair for him to stand in the way if FIU could get $100 million, so he withdrew his pledge and resigned from the Board of Trustees.